The present invention relates to a sewing machine capable of embroidery stitching, which is provided with a embroidery frame driving mechanism for driving a embroidery frame based on embroidery stitching data, and a display; and with respect to a large-size embroidery pattern larger than an embroidery area of the embroidery frame, capable of dividing into a plurality of divided patterns and performing embroidery stitching thereon, and a display control program for controlling the display on the display screen.
Conventionally, sewing machines capable of embroidery stitching, which perform embroidery-stitching operations while shifting a embroidery frame holding a cloth to be stitched freely in horizontal directions, have been put into practical use. In another type of sewing machine, a controller reads out embroidery stitching data with respect to a desired embroidery pattern selected by a user from a plurality of embroidery patterns and controls a embroidery frame driving mechanism, which drives the embroidery frame based on the embroidery stitching data; thus, the embroidery stitching operation is carried out. In this case, it is arranged so that a plurality of embroidery stitching data are previously stored in an internal storage such as nonvolatile memory provided to the controller, or read out from an external storage such as ROM card or flexible disk.
Recently, for sewing machines of this type, users are requesting to stitch larger embroidery patterns. To respond to such requests, a sewing machine capable of stitching large size embroidery patterns larger than the embroidery area of the embroidery frame has been considered. For example, in an embroidery data-creating means disclosed in Japanese Published Unexamined Patent Application No. 2000-24350, it has been disclosed to divide a large-size embroidery pattern into a plurality of partial patterns. And the embroidery data with respect to the respective divided patterns, which can be handled in one stitching operation, are created. Owing to this, even with a large size embroidery pattern, embroidery stitching can be made in several divided stitching operations.
In such sewing machines capable of embroidery stitching, an LCD display or the like is provided thereto. When a user selects an embroidery pattern and carries out the embroidery stitching operation, an image (configuration) of the embroidery pattern is displayed on the display. Owing to this, the user can check the embroidery pattern on the display.
When displaying an image (configuration) of an embroidery pattern on the display, generally, the display data with respect to each embroidery pattern is previously stored in a memory, and from the memory, necessary display data is read out and displayed on the display screen. Also, as a technique different from the above, another sewing machine, in which, display data is not stored in the memory, but based on the embroidery stitching data (data of needle location), a display data creating process is carried out to develop display data, and the pattern display data created in the display data creating process is displayed on the display, has been put into practical use.
However, in the former case where the display data is previously stored, to save the memory capacity or the like, the data amount of the display data per embroidery pattern is limited to a small amount. Therefore, only a rough configuration of the embroidery pattern is displayed in a relatively small size on the display. In the case of a relatively small embroidery pattern, even when the displayed image is rough, the user feels little inconvenience. However, in the case of the above-described large-size embroidery pattern, there reside the following disadvantages. That is, the user hardly recognizes the detailed configuration of the embroidery pattern using such a rough display; or, the image viewed on the display is different from the actually stitched embroidery pattern.
On the other hand, in the later case where the display data is created based on the embroidery stitching data through a display data creating process, a detailed image close to an embroidered state of the embroidery pattern can be displayed. However, particularly, in the case of a large-size embroidery pattern, there may be included such a precise embroidery pattern of which the number of stitching exceeds, for example, 100 to 200 thousand stitches. The size of the data amount to be handled is too large, and a significant amount of computing time is required for the display data creating process resulting in such a disadvantage that the embroidery pattern cannot be displayed swiftly on the display.